In this paper, an adaptive approach has been developed for automatic initialization of the thickening curve using machine vision technology, which makes it possible to determine with high accuracy the material parameters necessary for the design of thickening and clarification apparatuses. Software has been developed that made it possible to search for the coordinates of the condensation critical point in automatic mode. Studies on two samples of materials (tailings of apatite-containing ores and gold-bearing concentrate) were carried out and made it possible to statistically prove the reproducibility of the results obtained using the parametric criteria of Fisher and Bartlett. It has been established that the deposition curves are approximated with high accuracy by the Weibull model, which, together with the piecewise linear approximation, makes it possible to formalize the method for determining the critical point coordinates. The empirical coefficients of the Weibull model for two samples are found, and the final liquefaction and settling rates of the studied materials are determined.
The paper investigates present-day challenges related to accumulation, processing and disposal of the coal combustion wastes. The analysis of technogenic materials beneficiation practices using gravitation, magnetic and flotation beneficiation methods has been carried out. Quantitative and qualitative microscopic analysis of materials has been conducted. The study target were ash and slag wastes (ASW) from thermal power plant and coal combustion ash. Most metals are contained in coals and coal ashes in fine-dispersed (1-10 μm) mineral form. Various native metals and intermetallic compounds, sulfides, carbonates, sulfates, tungstates, silicates, rare earths phosphates and niobates have been discovered. Each metal may occur in several mineral phases, for instance tungsten may be in the form of wolframite, stolzite, ferberite, scheelite and represented by impurities. Not only composition of compounds is diversified, but also morphology of grains: well-defined and skeleton crystals, aggregates and polycrystalline structures, crystal twins and fragments; druses, globules and microspherules; porous shapes, flocculous and splintery clusters, lumpy aggregations, etc. Based on chemical silicate analysis of main ASW components the petrochemical properties of material have been assessed. Preliminary analyses have shown that concentration of ferrum-bearing components in ASW is around 5-11 %. The magnetic method of technogenic waste beneficiation with the help of high-gradient magnetic separation has been studied. The obtained evidences show that fine ASW are most efficiently separated in separators with high-gradient magnetic system. The studies provided justification of a process flow for complex treatment of technogenic carbon-containing material, including flotation, gravitation separation, magnetic heteroflocculation enrichment and high-gradient magnetic separation. The determined complex utilization ratio has proven the efficiency of complex processing.
It is well known that lime is an effective additive which allows to increase the depth and speed of the extraction of alumina from bauxite by the Bayer process. The firing is one of the operations in thermochemical conditioning of bauxite, it is rational to enter directly on the lime-stone at firing of bauxite, eliminating the special operation of firing limestone and calcined material damping. In order to test this were carried out research on the firing of bauxite in the presence of calcium oxide, subsequent desiliconization of calcined bauxite and autoclave leaching bauxite concentrate.
The results of the technical and mineralogical studies of washability of low quality bauxites of North Onega deposit are presented. The experiments of determination of the grindability of raw materials including without ball grinding and assessment washability bauxite by magnetic separation and flotation were conducted. These ores are very complex object for enrichment, as characterized by extremely thin impregnated aluminum-containing minerals, as well as the similarity of their properties. Further work of to conduct experiments using chemical enrichment (as soon as the chemical enrichment, and in combination with the physical methods of enrichment) is planned.
The possibility of thickening and filtration for separation of heterogeneous disperse systems formed during the chemical conditioning of bauxite was investigated. It is shown that with increasing the ratio between liquid and solid phases of bauxite pulp thickening process indicators are improving. A similar influence provides of temperature increase of the process and the use of flocculants. The obtained results are compared with the indicators of condensation of red mud. The filter cloth was chosen for slurry concentrate bauxite, which provides the most rational regime filtration with the accumulation of sediment.
The statistical analysis has allowed to reveal the additives essentially influencing process of formation of corundum. So, fluoric connections of sodium, calcium, aluminum, oxide of iron and chrome promote formation. Opposite influence is rendered oxide of sodium, by connections of lithium and a dioxide of the titan. Besides, influence of a dioxide of the titan and oxide of chrome is estimated.
In Russia and some other countries proposed various ways to the chemical enrichment of bauxite, which usually does not affect the question of regeneration of an alkaline solution of silica, or reduce it to the release of silica in the form of calcium silicate. While the technological circuits of the chemical enrichment of the return should include an alkaline solution, after regeneration, the following parties desiliconization bauxite. It is known that the chemical enrichment is accompanied by a secondary process – the formation of hydroaluminosilicates sodium, the rate of which depends on the concentration in the alkaline solution as aluminum oxide and silicon dioxide. This paper presents data a two-stage osazhdniya silica from an alkaline solution. In the first stage in the form of sodium hydro-aluminosilicates and second in the form of calcium silicate.
In article researches of kinetic and power characteristics of process of self-crushing which are executed on diamond-bearing ores of a deposit of a tube «Komsomolskaya» are resulted. Autogenous grinding process was investigated from a position of an exit of a commodity size –30 + 0,2 mm.
Materials of calculation of solubility of aluminum hydroxide in the system Na2O – K2O – Al2O3 – H2O, by data of the solubility in the private sections of this system for a wide range of compositions aluminate solutions by the content of alkaline components are presented. It is shown that the solubility of aluminum hydroxide in the range of concentration of alkaline components from 1,29 mol/l to 1,94 mol/l is a linear function of the mol fraction of one of them. The results of experimental researches on decomposition of aluminate solutions are given. Significant increase of the degree of decomposition of aluminate solutions in per cents of the theoretical values with growth of mol fraction of K2O in a mixture of alkaline components has been established.
In given article researches patterns of distribution and separation of bauxite substances by mechanical dispersion, which are executed on subprime Timan and the North Onega bauxite ores. The process of mechanical dispersion was considered the example of process of self-crushing.
The materials of mass transfer kinetic analysis of complicated by the establishment of adsorption equilibrium, during alumina liquor precipitation of alumina production. It is shown that the presence of strongly adsorbing impurities is one of the determinants of the intensity of the aluminum hydroxide chemical precipitation. The results of experimental studies on the alumina liquor precipitation with the participation of adsorption active components.
Results of desalination thermoactivated siliceous minerals alkali-containing are presented by solutions. Testify that at desilication bauxite it is observed gradual braking dissolution of a dioxide of silicon and alumina oxide at the expense of formation of a shielding layer. The increase in temperatures desalination roasting and the silicon module of initial bauxite leads to increase of factor of braking.
Results of desalination extraction chamoisite minerals alkali-containing are presented by solutions. It is shown that the behavior chamoisite at interaction with alkaline solutions depends on a parity orthogonal and monoclinic updatings and degree oxidation. However, prebaking in oxidizing medium these distinctions at the expense of almost complete decomposition chamoisite with formation amorphous aluminum and silicon oxides.
The method of automatic control over autogenous mill operation, allowing to raise productivity on an exit of a commodity class – 30 + 0,2 mm, and also to lower the expense of the electric power on ton of processed raw materials.
Experimental results of thermal deposition of crystal hydrates of magnesium sulfate from a solution containing sulphates of alkali metals. Set of indicators as a function of the kinetically relevant factors. It was shown possible to describe the crystallization kinetics equation of magnesium sulphate topochemical processes and identify its characteristics.
Results of desalination siliceous minerals alkali-containing are presented by solutions. Testify that that decomposition kaolin occurs in thickness of the firm phase covered with crust hydroalumosilicate of sodium, without breaking its basic structure and without surplus of solvent. The dissolved surface remains to a constant that is one of conditions of applicability of the equation of Drozdova – Rotinjana.
The algorithm and system optimal control of two-cycle by stages for mineral separation plant GMK «Pechenganickel». Computer modeling, which allows to determine the optimal set of optimization systems that implement the developed algorithm. A functional diagram of automation, allows the implementation algorithm and a system of optimal control.
Циклы измельчения проектируются для снижения крупности материала до величины, позволяющей при последующей сепарации частиц по тому или иному физическому свойству получить наилучшие технологические показатели. Их деятельность определяет эффективность, с которой передается энергия разрушения, общую эффективность всего передела рудоподготовки. Процесс измельчения наиболее энергоемкий и поэтому наиболее дорогой для типичной обогатительной фабрики. В настоящее время для моделирования процессов обогащения, в том числе и рудоподготовки, используются такие прогнозирующие пакеты как JKSimMet, UniCrugr и др.
Modeling of ore treatment processes allows selecting those options that contribute to cost and risk reduction. The use of universal forecasting software packages, such as JKSimMet, greatly facilitates and accelerates the calculation processes associated with the analysis of ore treatment schemes, saves not only time, but also money, giving the opportunity to consider many options with the subsequent selection of the most effective. In some cases, computer modeling is the only way to obtain reliable results.